This application is based on Patent Application No. 2000-319891 filed Oct. 19, 2000 in Japan, the content of which is incorporated hereinto by reference.
1. Field of the Invention
The present invention relates to a card connector mounted on electronic devices, such as cellular phones, telephones, PDAs (personal digital assistants), portable audio devices and cameras, and more specifically to a structure for locking a card ejection mechanism ejecting a card when the card is loaded.
2. Description of the Related Art
In electronic devices such as cellular phones, telephones, PDAs and cameras, a variety of functions are added by loading an IC card with a built-in CPU or memory IC, such as a SIM (subscriber identity module) card, an MMC (multimedia card) (trademark), an SD (super density) card, a Memory Stick (trademark) and a Smart Media (trademark).
The connector structure for removably accommodating such an IC card has a plurality of contact terminals in a connector housing that are connected to a variety of signal processing circuits and a power supply circuit of the electronic device on which the connector is mounted. These contact terminals are brought into contact with a plurality of contact pads formed on a front or back surface of the loaded IC card, causing the IC card to be electrically connected to the electronic device on which the connector is mounted.
Many of such card connectors have an ejection mechanism for withdrawing the loaded IC card from the connector.
A proposed system of this ejection mechanism is shown in FIG. 13.
The card connector shown in FIG. 13 has an ejection member 102 urged in an ejection direction by coil springs 100 to eject a card 101, a looking piece 103 adapted to engage with a locking projection 102a formed at an end of the ejection member 102 to restrict the movement of the ejection member 102 in the ejection direction, and an ejection button 104 for releasing the restriction imposed by the locking piece 103 to allow the card to be ejected. At the locking piece 103 is formed an engagement hole 103a for fixing the locking projection 102a. The ejection button 104 is urged in the ejection direction by a coil spring 105. The ejection button 104 has a cam surface 104a that displaces a front end of the locking piece 103 in a lateral direction C.
In the construction described above, with the card 101 loaded in the connector and the ejection member 102 held immovable by the locking piece 103 as shown in FIG. 13, when the ejection button 104 is depressed, the pressing force from the cam surface 104a displaces the front end of the locking piece 103 away from the locking projection 102a, disengaging the ejection member 102 from the locking piece 103, with the result that the ejection member 102 moves in the ejection direction by the force of the coil springs 100, which allows the loaded card 101 to extrude out of the connector.
There is a growing demand on the card connector of this kind for size reduction as the electronic devices are becoming smaller and smaller. To meet this demand a variety of parts need to be laid out efficiently in a small space.
In the card connector described above, however, since the front end of the locking piece 103 is displaced in the lateral direction C of the connector housing, it is necessary to secure a space in which to displace the locking piece 103 laterally. Further, the cam surface 104a of the ejection button 104 needs to be extended in the lateral direction C, which results in an increase in the width of the connector housing in the lateral direction C and therefore there are some problems that the mounting area of the connector increases.
The present invention has been accomplished under these circumstances and its primary object is to provide a card connector which can reduce the width of its connector housing and therefore the card mounting area.
According to one aspect, the present invention provides a card connector for holding a card in a connector housing in such a way that a plurality of contact pads provided on a bottom surface of the card are in contact with contact terminals arranged in the connector housing. The card connector comprises: an ejection mechanism having an ejection member, the ejection member being adapted to move in a card insertion direction as the card is inserted into the connector housing, and move in a card ejection direction in response to a card ejection operation to eject the card; a locking piece displaceable vertically of the connector housing and adapted to fix the ejection member, when the card is loaded, to restrict the movement of the ejection member in the card ejection direction; and an releasing means for unlocking the locking piece in response to the card ejection operation.
As described above, because the locking piece for locking the ejection member is displaced vertically of the connector housing to lock or unlock the ejection member, the present invention makes it possible to reduce the width of the connector housing and therefore the mounting area of the connector housing.
The above and other objects, effects, features and advantages of the present invention will become more apparent from the following description of embodiments thereof taken in conjunction with the accompanying drawings.